Just remember that a correct saddle position starts, first, by determining how far forward or back it goes on the saddle rails. This puts your knees in an optimal position with respect to the pedals. Once you have that determined, then it's a question of settling the saddle height. If you're only changing saddle height--by as much as a few inches--without regard to the saddle's fore/aft position, then you're not likely to get it set up very well. Now some people who've riding a long time and understand what geometry works for them, can do a decent job of setting a bike up without help, but a new rider might struggle with it.